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What do you mean by higher charge rooms? The ones that are larger in size or take the brunt of the sun?

Thanks,
Chip

I believe he said "higher load rooms" vs. "higher charge".

What he means is that rooms that have a higher heat load on them (from sun, door openings, larger expanses of glass, greater ceiling surface area, etc) will feel less cool more noticably when system capacity is reduced than rooms with a lower heat load.

An over or undercharge of refrigerant will reduce system capacity. If at any time a technician has tweaked the charge and did so by pressures only (or worse just put his hand on the suction line as he was charging until it got "beer can cold") then it's highly possible your system's charge is out of whack. This problem will only be aggravated if the system uses a fixed restrictor metering device rather than a thermostatic expansion valve, since fixed restrictor systems require a near critical charge (meaning it must be pretty much on the button for the system to operate at rated capacity).

You could have a compound problem. Airflow diminished to a few rooms combined with a tech who tweaked the charge, possibly influenced by a pressure reading that was off due to the airflow problem. This once again emphasizes why technicians need to make superheat and subcooling checks as much a part of their routine as carrying gauges in a service truck.

I'll repeat what I and others have said. If your system performed well for you for a year and then something changed, that something that caused the change needs to be found and remedied. Since the new ductwork didn't help matters any, the original problem is still there, waiting to be found.
The electrical problems appear unrelated to the performance issue. Sometimes these things crop up all at once, which seems confusing until someone with a cool head (no pun intended) sits down and puzzles through all the data to figure it all out.

Electricity makes refrigeration happen.

Refrigeration makes the HVAC psychrometric process happen.

HVAC pyschrometrics is what makes indoor human comfort happen...IF the ducts AND the building envelope cooperate.

Shophounds right about what I thought, Heres another thought. You metioned trans former replaced in air handler due to circuit breaker tripping.
If there is a problem with the air handler motor/blower, It could be running for a while,then trip on motors internal overload, cool, reset itself, and continue the cycle again. Have motor amperage and temperature checked as well on air handler.

i agree with shophound
have another co. look the system over. there have been alot of ideas and suggestions about this problem and bottom line is for the cause of this problem be found
if it worked properly for one year. then you had it repaired and now it doesnt work properly then something happened while it was being worked on. it could be anything from freon to ductwork. you have stated the airflo seems to be less in the two rooms then before
they installed more outlets and no change. i tend to still think dutwork. was it crushed, pulled apart. or not connected properly. did something get sucked into the blowerand block the return or block off part of the coil
did they slow down the blower. lenox comes with multy speed blowers. did someone but in a high air restricting filter. or is the charge wrong and the coil is freezing up and blocking the air.and many other posabilities.
now you are told inline register fans
call lenox and tell them what you have gone through and they will recommend a lenox dealer for you or set something up to help you out with this

Have you had any one in the attic crawling around other than our trade? cable, electrical,insulation,guys.ex husbands, (or wives,or kids, or others) The inner lining of flex can get trashed when crushed, leaving the outer lining looking good at a glance. Have inner lining checked by a pro.
I just found out my 12 yr old boy has another world in the attic.

Hey guys, it seems this system has one main return, and it seems this person moves stuff around in house room to room.Could it be some changes were made in other parts of house that has affected air flow return.Maybe a sort of zoning is occurring. Has a change been made between these two rooms and its access to the return? He did mention some areas were almost too cool.

Okay,
Had the owner of the company out today and his tech. They tell me the ductwork is undersized for the system, but it was always this way. I understand the house may not be cooling at it's optimum, but again, I'm just concerned about the change that happened last year. They really can't figure it out. Same tech that just did the yearly service on it, again checked everything and said the machine is working according to factory specs.

What they decided to do is put a booster fan in the 12 inch duct at the end of the house where the trouble is. It's just temporary to see if it resolves the problem. It was also suggested to keep the handler fan running at all times to keep air circulating better.

The front of the house is just now starting to get the hard afternoon sun. So far room is about 2 degrees warmer than other rooms. We'll see how this goes over the next few hot/humid days.

If this problem continues, we may have to switch companies. Thanks for all the input.
Chip

When I read that, your following words only made the above all that more painfully obvious:

What they decided to do is put a booster fan in the 12 inch duct at the end of the house where the trouble is.

What's that gonna do if there's a restriction upstream of the fan? Try and suck more air through an already cramped or obstructed path? Sounds to me like this company needs some serious air distribution training.

It was also suggested to keep the handler fan running at all times to keep air circulating better.

Great thing to suggest for a humid climate.

All along I keep going over that you said the system worked fine in the beginning, but then fell off. None of the repair efforts to date seem to take that into account. Do they just not believe you?

If this problem continues, we may have to switch companies.

And here comes the sticky part. You're basically still shooting craps with another company that you'll get someone competent enough to nail your problem. That shouldn't be the case.

If I were to walk into your home and you told me everything you've said here, I'd want to get a record of the system's airflow rate as well as evaluate the refrigeration circuit's performance. How painful is it for the airflow in the rooms in question to be measured? The tech doesn't have to bring along an expensive balometer to know what's going on. He can get an approximation with an anemometer and a little math. He can look in Manual J and see what CFM's a room sized comparably to the one in question should receive. If it's far off the mark, he'll know right off he has an airflow or air balance problem.

All that sounds worlds better than throwing on ducts and duct fans and staring at a gauge manifold and then saying let's hope for the best.

Electricity makes refrigeration happen.

Refrigeration makes the HVAC psychrometric process happen.

HVAC pyschrometrics is what makes indoor human comfort happen...IF the ducts AND the building envelope cooperate.

Hi again,
What they're telling me is that the problem is the ducts are not sized properly. You see we have a very small truss/ crawl space over a landing, and it runs about 15-20 ft. No one can replace the ductwork through there because they can't get in there to even hook up the two ducts that run out to the living room. So they are saying the ductwork is not right for the system. They didn't tell us that when they installed the new handler and compressor. They just asked how the rooms cooled with the current system, and we said our back bedroom (not in the sun) gets a little warm. So when they installed the new a/c units, they changed the return from the back bedroom and ran it straight to the handler. That fixed that problem. The whole end of our house has always been a few degrees warmer than the main. It was no big deal though, it was still livable. Last summer my front office got up to 86 degrees. Maybe they don't believe me. They just keep saying air flow problem.

So I think this is how it runs. Air handler is at one end of house by the kitchen, d/r and great room. All cool fine. I think there is 12" supply starting from the handler. The part over the landing that they can't replace (unless they tear out wall/ceiling . . . major work), is only 9" which previously went to 1-8", 2-6" and 2-4" ducts that supplied 3 bedrooms, 2 baths and one master closet. There is a crawl space again above the end of the house past the landing. So, just recently at the end of the landing where the 9" supply is coming out from the landing crawl space, they cut it and placed a 12" again, and added a different junction/mixing box. That didn't seem to do anything, and that's what cost $600. So now they stuck a fan in the new 12" section. There is still the 9" supply coming over that landing though. They tell me the only real solution is to replace that 9" which they really can't get to without a major headache and major expense to me.

Okay for optimal supply maybe they need to do that, but like I said, the new unit and previous unit cooled sufficiently. So they're not really changing their song. That's why if this doesn't solve it, we're really going to have to find someone else.

I don't know if the tech today really got all good readings. I mean if he didn't and found something else, he'd have to admit he goofed, and with the boss here, I'm doubting he'd want to do that. I don't know. If everyone were totally honest, that would be wonderful. But it's not a perfect world, and obviously, A/C isn't a perfect science either.

If this fan helps, than I don't care if it's the best thing to do or not. My only concern is does this present any type of fire hazard. We're in hot FL, so the attics are really warm in the summer.

The new air handler worked fine the first year it was installed in 2003. Spring/ summer of 2004 was when we had the problem. There are two vents in the great room, and yes, I think it is a 9" supply. The tech took his picture with him, I'll ask him to fax it back. It could be 11", I forget now, so much info But when it came to the end of the landing it did go down to a 9". That's what they cut off and changed to 12". So what is over the landing may be 10 or 11, not 9. I'll see if I can find more info.

Originally posted by chipper The new air handler worked fine the first year it was installed in 2003. Spring/ summer of 2004 was when we had the problem. There are two vents in the great room, and yes, I think it is a 9" supply. The tech took his picture with him, I'll ask him to fax it back. It could be 11", I forget now, so much info But when it came to the end of the landing it did go down to a 9". That's what they cut off and changed to 12". So what is over the landing may be 10 or 11, not 9. I'll see if I can find more info.

Chip

Not sure if this can work,but it might.

Can you run new supply grilles to the greatroom area,on the side closer to the air handler,where the attic may be larger?If you can,then remove the grilles from the existing greatroom ceiling ,plug them and replace the grilles.

Now the air that was going to the greatroom ,will be directed to the problem area,and you'll have new runs to the greatroom ,coming of a larger duct,closer to the air handler.

We have done this with success,when some of the ducts are inaccessable.